Efforts to ratify the New START nuclear arms reduction treaty in the U.S. Senate received a boost Friday. Two more opposition Republican Senators say they will vote for the treaty, and the White House is expressing new confidence that it will pass this year.

Republican Senators Olympia Snowe and Susan Collins have announced their support for the treaty, which would shrink the U.S. and Russian nuclear arsenals.

In a written statement, Snowe said she is confident that New START will add predictability to the U.S. relationship with Russia.

The Senate's top Republican negotiator, Jon Kyl, has said there is not enough time in this year's session to ratify the agreement.

But fellow Arizona Republican John McCain said Friday he hopes the Senate will be able to consider the treaty in the coming week.

McCain spoke Friday at the Johns Hopkins University School for Advanced International Studies in Washington.

"My colleague, Senator Jon Kyl, is doing a tremendous job working with the administration to resolve the issues associated with nuclear modernization," he said. "I have been focusing my efforts on addressing the key concerns related to missile defense. I think, we are very close to agreements."

However, McCain also questioned the wisdom of President Barack Obama's efforts to "reset" relations with Russia, and urged leaders to take a wider look at the relationship between the two countries.

At the White House, the president's spokesman, Robert Gibbs, told reporters Friday Congress will not end its session before the Senate ratifies New START, and that Mr. Obama will not leave for vacation until it does. The president is scheduled to depart Washington for his home state of Hawaii on December 18.

One day earlier, Gibbs predicted the treaty would pass the Senate before the end of the year with more than the 67 votes needed.

"When was the last thing we proposed that the last six Republican secretaries of state thought was a good idea, that did not have the vast support of the American people like START does? It is the right thing to do for our relationship with Russia and our relationships in the world," said Gibbs. "It is the right thing to do to cut our deployed nuclear stockpiles. I think it will get done because of that."

All the Senate's Republicans signed a letter last week, saying the tax cut issue must be resolved before they would consider any other legislation.

If the treaty is not ratified this year, the process will start again from the beginning in 2011, with a larger group of minority Republicans in the Senate.